<template>
    <!-- 输入框 -->
    <header class="header">
      <h1>小黑记事本</h1>
      <input 
      @keyup.enter="handleAdd"
      v-model="todoName" placeholder="请输入任务" class="new-todo" />
      <button @click="handleAdd" class="add">添加任务</button>
    </header>
</template>
<script>
export default {
    data (){
        return {
            todoName:''
        }
    },
    methods: {
        handleAdd (){
if(this.todoName.trim===''){
alert('任务名称不能为空')
return
}
this.$emit('add', this.todoName)
this.todoName=''
}
}
}
</script>

<style>

</style>